Percy William Whitlock (1 June 1903 – 1 May 1946) was an English organist and post-romantic composer. He was born in Chatham, Kent, and was a student of Vaughan Williams at London's Royal College of Music. He quickly arrived at a musical idiom that combined elements of his teacher's output and that of Elgar. His lush harmonic style also bore traces of Gershwin and other popular composers of the 1920s, and there were other important stylistic features from such figures as Stanford, Rachmaninov and Roger Quilter. Like Vaughan Williams and Frederick Delius, he often used themes that sounded like folk songs but were, in fact, original creations.

From 1921 to 1930 he was assistant organist at Rochester Cathedral, before serving as Director of Music at St Stephen's Church, Bournemouth for the next five years, while combining this from 1932 with the role of that town's borough organist.

Among his organ works are Five Short Pieces (1929), Four Extemporisations (1933), Seven Sketches on Verses of the Psalms (1934), the Plymouth Suite (1937–1939) and the Sonata in C minor (1936). His creative gifts expressed themselves most completely in the smaller forms, and as a miniaturist he can stand alongside many composers much better remembered than he.

He was diagnosed with tuberculosis in his twenties, and also suffered from hypertension. Near the end of his life he lost his sight altogether, and he died in Bournemouth a few weeks before his 43rd birthday. For decades afterwards he remained largely forgotten. This neglect has eased in recent times, with the increased popularity of post-romantic organ literature.